https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104099
--- Comment #1 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jonathan Wakely <r...@gcc.gnu.org>: https://gcc.gnu.org/g:fe3ed885cda5ab920d361b694ee539242052022f commit r12-6698-gfe3ed885cda5ab920d361b694ee539242052022f Author: Jonathan Wakely <jwak...@redhat.com> Date: Tue Jan 18 16:26:45 2022 +0000 libstdc++: Limit new basic_string(nullptr_t) constructor to C++23 [PR104099] The new deleted constructors added by P2166R1 are a breaking change, making previously valid code ill-formed in C++23. As a result, they should only be defined for C++23 and not for C++11 and up. libstdc++-v3/ChangeLog: PR libstdc++/104099 * include/bits/basic_string.h (basic_string(nullptr_t)): Only define for C++23. (operator=(nullptr_t)): Likewise. * include/bits/cow_string.h: Likewise. * include/std/string_view (basic_string_view(nullptr_t)): Likewise. * testsuite/21_strings/basic_string/cons/char/nullptr.cc: Adjust expected error. Add examples that become ill-formed in C++23. * testsuite/21_strings/basic_string_view/cons/char/nonnull.cc: Adjust expected errors. * testsuite/21_strings/basic_string_view/cons/wchar_t/nonnull.cc: Likewise.
